Well , I'm trying to solve some exams, and I have some difficulties in the following questions:

1. Let A = where p,q are disjoint primes.

Prove that there arem,n such as n|m and A is isomorphic to:unique

.

I've no clue about this one.

2. Let F be a field.

Prove that $\displaystyle \frac{F[x_{1},x_{2}]}{(x_{1})} isomorphic F[x_{2}] $

I realy need your guidance in these ones.

Thanks in advance